Apparatus for burning liquid fuels



March 14, 1944. H, LLOYD 2,344,439

APPARATUS FOR BURNING LIQUID FUILS Filed Aug. 25, 1941 2 Sheets-Sheet 1 2 I17 Z3 z4 March 14, 1944. H. c. LLOYD 2,344,439

APPARATUS FOR BURNING LIQUID FUELS Filed Aug 25, 1941 2 Sheets-Sheet 2 Patented Mar. 14, 1944 UNITE TES OFFICE 5 Claims.

This invention appertains t an improved apparatus for burning liquid fuels, and more especially to an apparatus which is primarily intended for use in burning low-grade oils, although it is to be understood that the invention is not limited to this field.

There has long been a demand for, a low-cost, economical and efficient burner capable of operation with low-grade oil, and the present invention has been developed to meet this demand which it fulfills far better than any burner heretofore available. Due to my improved method of forming a combustible mixture as will hereinafter be more specifically described, and the novel features of the burner as employed in the practice of such method, my invention can be very successfully operated with waste and reclaimed oil, as well as with any of the usual grades of fuel oil from No. l to No. 6, inclusive.

IAS a typical example of waste oil which may be employed with my new burner, ordinary crank case 011 as drained from automobile engines and other internal combustion engines can be burned emciently and with marked success to produce an intense heat useful for space heating, home heat- 1 ing, hot water heating, and numerous industrial purposes where heaters are required. The crank case oil may be burned in its waste state without preliminary treatment or it may be initially reclaimed or mixed with other low-grade oils where preferred. Because of its adaptability to the use of waste oil in an untreated state, my invention finds an extensive field of use for heating purposes in and around gasoline stations, garages and the like where waste oil is accumulated in large quantities at substantially no cost to the proprietor or owner.

Another typical and satisfactory fuel which may be successfully used with my burner is the industrial grade of oil commonly known as Bunker C. This fuel is reclaimed oil which is rather extensively used for industrial purposes, and is sold for a very low price, much lower than the price of the usual fuel oils.

In the burning of alll of the various low-grade oils to which my invention is applicable, the oil is burned cleanly and produces an intensely hot flame. No carbonization takes place and no deposit is formed in the burner as is commonly found in most of the present day oil burners, requiring periodical cleaning and chipping out.

One of the primary objects of the invention is to provide an improved apparatus for roducing a combustible mixture wherein air is forced at or pool of liquid fuel and thereafter the air and gases evolved on ignition of the liquid fuel are caused to be intimately mixed by a whirling motion imparted to the air and flame within a combustion chamber.

To the foregoing end, the apparatus for burning low-grade oil preferably has the form of a generally cylindrical upright combustion chamber having an outlet at its upper end and provided with air and fuel inlets at its lower end, the fuel inlet communicating with a well at the bottom of the combustion chamber and the air inlet communicating with a blower or other comparable source of air supply, arranged to direct the air at relatively high velocity over the surface of the fuel in the well and in a direction offset to one side of the central axis of the combustion chamber so as to cause the flame on ignition of the fuel in the well to be rapidly whirled about the central axis of the combustion chamber, and thereby cause a sufiicient and intimate mixture of air with the volatilized fuel to produce an intensely hot flame with complete combustion of the fuel, and elimination of smoke and offensive odors.

Other and further objects and advantages of the invention will be hereinafter described, and the novel features thereof defined by the appended claims.

In the drawings:

Figure l is a top plan view of a liquid fuel burning apparatus embodying the features of my invention as used in a typical installation, the burner proper being shown connected with a conventional blower for delivering air thereto, and also connected with a fuel line having suitable controls which are illustrated somewhat diagrammatically, certain of the parts of the figure being broken away and shown in section;

Figure 2 is an enlarged View, partly in side elevation and partly in vertical section, of the burner structure;

Figure 3 is a view in end elevation as viewed from the righthand side of Figure 2.

Figure 4 is a horizontal sectional view taken about on the line l4 of Figure 3;

Figure 5 is a fragmentary vertical sectional view taken about on the line 55 of Figure 4; and

Figure 6 is a fragmentary vertical sectional view taken about on the line ii-fi of Figure 4.

Like reference characters designate corresponding parts in the several figures ofv the drawings.

In Figure 1, the general assembly of the aprelatively high velocity over the surface of a well no paratus has been illustrated in a form typical for use as an installation in a stove, domestic furnace, hot water heater, or industrial heating equipment, the details of which are unnecessary to a full understanding of my invention, and for which reason have not been shown. According to Figure l, the reference character I denotes the burner proper to which a fuel line 2 is connected, as well as an air duct 3 leading from a blower 4 or other suitable source of air supply by means of which air may be delivered at relatively high velocity to the burner. The blower is shown in Figure 1 attached to a plate 5 having a suitable opening therein and communicating with the air duct 3. This plate 5 in the assembly of the apparatus in a stove or furnace, as the case may be, may be substituted for the ash pit or fire box door, or otherwise mounted over an opening in the side of the stove or furnace through which the necessary connections tothe burner may be extended when the burner has been properly positioned in the stove or furnace. This detail is obvious and well lmown, and may be varied to suit the various pieces of equipment which maybe encountered in the installation of my new apparatus.

The burner proper preferably has the form of a generally cylindrical casing or housing 6 arranged with its central axis upright, the housing being closed at its bottom by a bottom wall 1, and provided at its upper end with a removable cover 8 having an opening 9 therein, forming an outlet for the products of combustion produced within the combustion chamber defined within the housing. The cover 8 may be varied in shape and the manner of its attachment to the housing 6 may also be varied if desired. However, as shown in the drawings, the cover is annular in form and is seated in a recess Ill formed in the marginal flange ll provided at the upper end of the housing, so that the cover 8 lies substantially flush with the extreme upper end of the housing. Screws [2, 12 or other suitable fastenings may be employed to positively retain the cover in place on the burner and prevent its inadvertent displacement. Both the housing and the cover may be made as castings of iron, steel or any suitable material of sufficient strength and capable of withstanding the heat to which the same will'be subjected when in use. As the description hereinafter proceeds it will be seen that the simplicity of the burner construction lends itself to the important advantage of low cost of production.

Adjacent to the bottom of the housing 6 I preferably provide a plurality of radially offset lugs or bosses I3 which are apertured vertically to receive adjustable legs M which may conveniently have the form of cylindrical rods or bars. Each lugor boss may be provided with a setscrew l5 suitably threaded therein to grip the associated leg I 4 on tightening of the set-screw when the burner has been brought to the desired elevation above the surface on which the legs rest within the stove, furnace, or other enclosure.

Extending from one side of the housing 6 near the bottom thereof, and offset to one side of the vertical axis of the housing, is a tubular extension it which forms the air inlet for the combustion chamber within the housing. The position of the extension i5 is such that on passage of air therethrough and into the combustion chamber, the air will follow the cylindrical wall of the housing and thereby assume a whirling motion within the combustion chamber about the vertical axis of the chamber. This feature is of prime importance to the utility and high efficiency of my invention as will hereinafter more fully appear.

The lower part of the extension l6 departs from the generally tubular shape of the extension and has the form of a well I! which is offset from the corresponding side of the housing 6 and lies directly below the air intake passage formed by the extension I6. The well I! is separated at its inward end from the combustion chamber by a dam l8, and the bottom of the well is provided with a fuel inlet to which the fuel line 2 is adapted to be connected to direct the liquid fuel into the well from some convenient source of supply such as a storage tank (not shown). The dam I8 is preferably made of such height that the depth of the oil entering the well I! through the fuel line 2 will not substantially exceed 4 of an inch more or less. As the oil rises in the well I! to the top of the dam [8, any further flow of oil will cause the same to overflow the dam into a second well 19 provided at the bottom of the combustion chamber in line with the general path of the air entering the combustion chamber through the air inlet. As best shown in Figures 4 to 6, the bottom of the well 19 is somewhat lower than the bottom 'I of the housing 6, and while the bottom of the well 19 is preferably horizontal, the inner walls of the well preferably vary in height along the line A, B, C. From the point A to the point B, the height of the bottom 1 above the bottom of the well I9 is preferably uniform, as for example about of an inch, but from the point B to the point C, this height is progressively reduced to approximately of an inch. Therefore, should the well l9 become filled with oil, it will overflow from the well onto the bottom I of the housing 6 near the point C, and if the overflow should increase, it will progressively flow onto the bottom 1 along the line from C to B. If desired, the bottom 1 may be inclined slightly towards the well l9 so that any oil accidently or otherwise deposited on the bottom will be returned automatically to the well l9.

Arranged in the wells I! and I9 is a wick 20,

the Wick being of any suitable type having a flat 7 form so that it may lie on edge, with its upper edge extending above the oil level in the wells l1 and I9. Through the use of the wick, flooding of the burner on starting is avoided, and the wick further serves to carry the flame from the well l1 over into the well 19 in the combustion chamber, thereby preheating the combustion chamber, and particularly the well I9 before the oil passes into the same on starting of the burner.

Referring to Figures 3 and 4, I have shown a bafile 2| comprising a rectangular perforate screen arranged in the air inlet defined by the extension I6, and located directly above the well I1. This baille screen serves to substantially prevent the air from blowing directly against the oil in the well I! as the air enters the burner, thereby allowing the temperature of the flame occurring in the well I! to be maintained relatively high and thus increase the efliciency of combustion of the oil in the combustion chamber where the combustion principally takes place. function of the bafile screen 2| is not fully understood by me, I have found that its use produces a very beneficial effect on the combustion and heat output of the burner.

As previously mentioned, the air directed to the air inlet of the burner may be derived from While the any suitable source such as the blower 4. As il- .lustrated in Figure 1, the blower may be of a conventional type embodying a rotary impeller, not shown, driven by an electric motor 22 and having an adjustable gate or shutter 23 associated with its air intake to permit variation of the volume of air delivered to the burner. The gate or shutter 23 is illustrated as being pivotally adjustable about the pivot screw 24. This adjustment may be manual or automatic as preferred. If desired, a spiraling motion may be imparted to the air passing from the blower 4 to the burner as by providing a plurality of spiral blades 21 within the duct 3 intermediate the blower and the burner. As shown in Figure 1, these blades may have the form of a short insert wherein the blades are mounted on the interior of an annular sleeve 28. The spiral motion imparted to the air by the blades 21 will additionally improve the efficiency of combustion of the fuel, although the use of the blades is not essential to the satisfactory operation of the burner.

Likewise, the control of the fuelflowing to the burner through the fuel line may be manual or automatic as Will be obvious to those skilled in the art. I have diagrammatically illustrated in Figure 1 a cut-01f valve 25 disposed in the fuel line and an automatic levelling device designated 26 to control the level at which the oil is permitted to rise in the oil wells of the burner. This levelling device 26 can be a standard fuel oil levelling valve-having a metering stem for manual control, and/or provided with suitable thermostatic controls. Such devices are well known in the art and need not therefore be further described.

The operation of my improved apparatus will be obvious from the foregoing description, and may be briefly summarized as follows. To initially start the burner, the cut-off valve 25 in the fuel line 2 should be opened and the manual or automatic fuel controls 26 should be set so that the oil may flow through the fuel line 2 into the well I! at the inlet side of the burner. When a sufficient quantity of oil has entered the Well IT, the wick 2%] may be lit in any suitable manner. Access to the wick may be had through the opening 9 in the cover 8 on the top of the burner, or by temporarily removing the cover and subsequently replacing the same as permitted by the screws i2, i2. After the wick has been ignited, the blower 4 should be set in operation and its gate or shutter 23 regulated to supply as much air through the air inlet of the burner as is necessary to produce combustion of the fuel according to the rate of flow of fuel to the burner. By limiting the flow of oil through the fuel line 2 to a very small amount through means of the manual or automatically controlled fuel valve 26, the flame can be reduced to a pilot flame which will be held steady by the wick 251. Under such conditions, the gate or shutter 23 should be adjusted manually or by means of suitable automatic controls to reduce to a minimum the amount of air delivered to the burner by the blower. On increase of the flow of oil to the burner when a greater output of heat is required, the oil level in the well ll will rise and overflow into the well l9, accompanied by a manual or automatic opening of the shutter 23 to increase the flow of air to the burner. As the air enters the creased until ultimately the flame will assume a burner, it passes above the perforated baflle screen 2| and enters the combustion chamber above the well l9. As the temperature is raised in the combustion chamber, the length of the flame is inrapidly whirling motion within the combustion chamber due to the corresponding motion of the air, and the air will become thoroughly mixed with the gases evolved and so enveloped within the whirling flame that complete combustion of the fuel will take place as rapidly as the fuel is fed to the burner. The products of combustion may escape from the combustion chamber through the opening 9 in the cover 8 at the upper end of the burner. If the fuel feed is increased sufficiently, the rapidly whirling flame may be caused to substantially completely flll the combustion chamber and even extend upwardly through the outlet 9 at the top thereof and rise a considerable distance above the burner.

By suitably controlling the rate of feed of the fuel and corresponding rate of feed of the air, the size of the flame and the heat output of the burner may be regulated to the desired amount and kept steady or varied as required. When properly regulated, no smoke or ofiensive odors will be given off by the burner, and oils even of the low-grade such as waste or reclaimed oils, will burn cleanly and leave no deposit in the burner, regardless of the extent to which the oil is fed to the well 19 in the combustion chamber or overflows from this well onto the bottom of the combustion chamber at the side of this well. It is largely due to the rapid whirling motion imparted to the air and flame within the combustion chamber that the high efficiency and high economy of my burner is attained.

While the specific details have been herein shown and described, the invention is not confined thereto, as changes and alterations may be made without departing from the spirit thereof as defined by the appended claims.

I claim:

1. Liquid fuel burning apparatus of the class described, comprising a housing forming a generally cylindrical, upright combustion chamber having an opening at its top and having an air inlet adjacent its bottom and projecting outwardly therefrom beyond the vertical Wall of the housing, said air inlet opening into the combustion chamber at one side of the vertical axis of the same and arranged to direct the air along the wall of the housing with a whirling motion about its vertical axis, said housing having a well in the bottom of the projecting air inlet provided with a fuel inlet, said well including a darn between the fuel inlet and the combustion chamber within the housing, a second well in said housing at the bottom of the combustion chamber to receive fuel for combustion in the combustion chamber from the first mentioned Well by overflow from the latter over the dam, a source of liquid fuel connected to the inlet of the first mentioned well, and a blower connected to the air inlet of the housing for directing air at relatively high velocity over the wells and with a rapid whirling motion within the combustion chamber to produce an intimate mixture of air and gases evolved on ignition of the fuel and cause complete combustion of the fuel in the form of an intense flame.

2. Liquid fuel burning apparatus of the class described, comprising a housing forming a generally cylindrical, upright combustion chamber having an opening at its top and having an air inlet adjacent its bottom, said air inlet opening into the combustion chamber at one side of the vertical axis of the same and arranged to direct the air along the wall of the housing with a whirling motion about its vertical axis, a well formed in said housing below the air inlet and having a fuel inlet, said well including a dam between the fuel inlet and the combustion chamber, a second well formed in said housing at the bottom of the combustion chamber to receive fuel from the first-mentioned well by overflow from the latter over the dam, a wick extending from the firstmentioned well into the well at the bottom of the combustion chamber, with a portion of said wick projecting above the normal fuel level in said wells, a source of 1iquid fuel connected to the inlet of the first-mentioned well, and a blower connected to the air inlet of the housing for d-irecting air at relatively high velocity over the wells and with a rapid whirling motion within the combustion chamber to produce an intimate mixture of air and gases evolved on ignition of the fuel and cause complete combustion of the fuel in the form of an intense flame.

3. Liquid fuel burning apparatus of the class described, comprising a housing forming a generally cylindrical, upright combustion chamber having an opening at its top and having an air inlet adjacent its bottom, said air inlet opening into the combustion chamber at one side of the vertical axis of the same and arranged to direct the air along the wall of the housing with a whirling motion about its vertical axis, a'well formed in said housing below the air inlet and having a fuel inlet, said well including a dam between the fuel inlet and the combustion chamber, a second well formed in said housing at the bottom of the combustion chamber to receive fuel from the first-mentioned well by overflow from the latter over the dam, a perforated bafile disposed in the air inlet above the first-mentioned well, a source of liquid fuel connected to the inlet of the first-mentioned well, and a blower connected to the air inlet of the housing for directing air at relatively high velocity over the wells and with a rapid whirling motion within the combustion chamber to produce an intimate mixture of air and gases evolved on ignition of the fuel and cause complete combustion of the fuel in the form of an intense flame.

4. Liquid fuel burning apparatus of the class described, comprising a housing forming a generally cylindrical, upright combustion chamber having an opening at its top and having an air inlet adjacent its bottom, said air inlet opening into the combustion chamber at one side of the vertical axis of the same and arranged to direct the air along the wall of the housing with a whirling motion about its vertical axis, a well formed in said housing below the air inlet and having a fuel inlet, said well including a dam between the fuel inlet and the combustion chamber, a second well formed in said housing at the bottom of the combustion chamber to receive fuel from the first-mentioned well by overflow from the latter over the dam, the bottom of the combustion chamber adjacent to the second-mentioned well being inclined towards the latter well in said chamber, a source of liquid fuel connected to the inlet of the first-mentioned well, and a blower connected to the air inlet of the housing for directing air at relatively high velocity over the wells and with a rapid whirling motion within the combustion chamber to produce an intimate mixture of air and gases evolved on ignition of the fuel and cause complete combustion of the fuel in the form of an intense flame.

5. A burner structure for the combustion of liquid fuels, comprising a housing forming a generally cylindrical, upright combustion chamber having a restricted opening at its top and having an air inlet adjacent its bottom, with the air inlet projecting outwardly from the vertical wall of the housing and arranged substantially at a tangent thereto so as to direct the air along the wall of the housing Within the combustion chamber with a whirling motion about its vertical axis, a well formed in the bottom of said air inlet in exteriorly spaced relation to the combustion chamber within the housing, said well having a fuel inlet and also having a dam disposed between the fuel inlet and the combustion chamber Within the housing, a second well in said housing at the bottom of the combustion chamber to receive fuel for combustion in the combustion chamber from the first-mentioned well by overflow from the latter over the dam, and a wick disposed in at least one of the wells aforesaid, said wick being of such height as to project above the normal fuel level in its well.

HARRY C. LLOYD. 

